Segment Information - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment	3
Segment Reporting Information [Line Items]
Property and equipment, net	$ 48,866	$ 29,114	$ 21,838
United States
Segment Reporting Information [Line Items]
Property and equipment, net	35,500	22,000	16,800
Rest of world
Segment Reporting Information [Line Items]
Property and equipment, net	$ 13,400	$ 7,100	$ 5,000